EP3526017A1 - Method for producing contact lenses - Google Patents
Method for producing contact lensesInfo
- Publication number
- EP3526017A1 EP3526017A1 EP17797740.2A EP17797740A EP3526017A1 EP 3526017 A1 EP3526017 A1 EP 3526017A1 EP 17797740 A EP17797740 A EP 17797740A EP 3526017 A1 EP3526017 A1 EP 3526017A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- mold
- lens
- mold half
- silicone hydrogel
- female mold
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
- B29D11/00—Producing optical elements, e.g. lenses or prisms
- B29D11/00009—Production of simple or compound lenses
- B29D11/00038—Production of contact lenses
- B29D11/00125—Auxiliary operations, e.g. removing oxygen from the mould, conveying moulds from a storage to the production line in an inert atmosphere
- B29D11/00192—Demoulding, e.g. separating lenses from mould halves
- B29D11/00221—Demoulding, e.g. separating lenses from mould halves using prying means
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
- B29D11/00—Producing optical elements, e.g. lenses or prisms
- B29D11/00009—Production of simple or compound lenses
- B29D11/00038—Production of contact lenses
- B29D11/00125—Auxiliary operations, e.g. removing oxygen from the mould, conveying moulds from a storage to the production line in an inert atmosphere
- B29D11/00192—Demoulding, e.g. separating lenses from mould halves
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
- B29D11/00—Producing optical elements, e.g. lenses or prisms
- B29D11/00009—Production of simple or compound lenses
- B29D11/00038—Production of contact lenses
- B29D11/00125—Auxiliary operations, e.g. removing oxygen from the mould, conveying moulds from a storage to the production line in an inert atmosphere
- B29D11/0023—Transferring contact lenses
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
- B29D11/00—Producing optical elements, e.g. lenses or prisms
- B29D11/00009—Production of simple or compound lenses
- B29D11/00038—Production of contact lenses
- B29D11/00125—Auxiliary operations, e.g. removing oxygen from the mould, conveying moulds from a storage to the production line in an inert atmosphere
- B29D11/0023—Transferring contact lenses
- B29D11/0024—Transferring contact lenses using a vacuum suction gripper
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- G—PHYSICS
- G02—OPTICS
- G02C—SPECTACLES; SUNGLASSES OR GOGGLES INSOFAR AS THEY HAVE THE SAME FEATURES AS SPECTACLES; CONTACT LENSES
- G02C7/00—Optical parts
- G02C7/02—Lenses; Lens systems ; Methods of designing lenses
- G02C7/04—Contact lenses for the eyes
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
- G02B1/04—Optical elements characterised by the material of which they are made; Optical coatings for optical elements made of organic materials, e.g. plastics
- G02B1/041—Lenses
- G02B1/043—Contact lenses
Definitions
- the present invention is related to an improved method for producing contact lenses, in particular silicone hydrogel contact lenses. .
- Contact lenses such as silicone hydrogel contact lenses, can be any suitable contact lenses.
- Contact lenses such as silicone hydrogel contact lenses.
- a conventional full-mold process involving disposable molds the examples of which are disclosed in, for example, PCT patent application publication no. WO/87/04390, in EP-A 0 367 513 or in U.S. Patent No. 5,894,002.
- a predetermined amount of a polymerizable or crosslinkable material typically is introduced into a disposable mold including a female (concave) mold half and a male (convex) mold half.
- the female and male mold halves cooperate with each other to form a mold cavity having a desired geometry for a contact lens.
- polymerizable or crosslinkable material may be used so that when the male and female halves of the mold are closed it is ensured that the mold cavity is
- the polymerizable or crosslinkable material remaining within the mold is polymerized or cross-linked by means of actinic radiation (e.g. , UV irradiation, ionized radiation, microwave irradiation or by means of heating. Both the starting material in the mold cavity and the excess material in the overflow area are thereby hardened. Subsequently, the mold is opened and the polymerized but as yet unhydrated contact lens is removed and further processed.
- actinic radiation e.g. , UV irradiation, ionized radiation, microwave irradiation or by means of heating.
- this strong adhesion is due to the tackiness of the surface of the lens, such as a silicone hydrogel lens, so produced.
- the lens can adhere to itself (curl) and lens handling can be difficult, and/or the lens can be damaged or torn due to extreme surface tackiness and strong adhesion to the surface of the mold half.
- the partial or initial washing with organic solvent can help deblock (or dislodge, or delens) the lens.
- the removed lens may further be subjected to other process, such as, for example, further extraction/washing, plasma treatment, hydration, sterilization, etc.
- An organic solvent such as, e.g., isopropyl alcohol (IPA)
- IPA isopropyl alcohol
- the solvent swells the lens and helps reduce the forces holding the lens to the mold half surface.
- an organic solvent e.g., IPA
- the lens after swelling in an organic solvent may still be sticky or tacky.
- PCT published international patent application No. WO 01/30558 describes a different approach for dislodging a lens from its adhering mold half, by lowering the temperature of the contact lens with a cryogenic material to a temperature and for a time sufficient for the lens to release from its adhering mold half without the application of external forces.
- the lowering of the temperature of the contact lens is accomplished by direct or indirect contact with a cryogenic substance, such as liquid nitrogen, liquid helium, liquid carbon dioxide, or solid carbon dioxide ("dry ice").
- a cryogenic substance such as liquid nitrogen, liquid helium, liquid carbon dioxide, or solid carbon dioxide ("dry ice").
- Tg glass transition temperature
- the surface tackiness temporarily freezes. This makes the lens separate from the mold half because of reduction in the tackiness and probably lens size reduction.
- the lens after separation becomes tacky again in air, which makes the lens handling difficult.
- use of a cryogenic substance can increase product cost.
- the invention is directed to a method for producing contact lenses, including: a) providing a mold including a male mold half having a first molding surface and a female mold half having a second molding surface, wherein the male and female mold halves are configured to receive each other such that a mold cavity is formed between the first and second molding surfaces when the mold is closed; b) dispensing an amount of a silicone hydrogel lens-forming material into the female mold half; c) mating the male and female mold halves to close the mold; d) curing the silicone hydrogel lens-forming material located in the mold cavity, thereby forming a molded silicone hydrogel contact lens; e) separating the mold into the male and female mold halves, with the silicone hydrogel contact lens adhered on one of the male and female mold halves; f) holding the molded silicone hydrogel contact lens attached to the one of the female mold half or the male mold half with a vacuum supplied with a suction cup; g) deforming a surface of the one of the female mold half or the male mold half having the
- the invention is also directed to an apparatus for delensing silicone hydrogel contact lenses from the lens adhering mold half, the apparatus comprising: a mold half holder, wherein the mold half holder holding a molded silicone hydrogel contact lens seated on the top of one of the female mold half or the male mold half, a suction cup, wherein the suction cup connecting with the mold half holder and contacting the molded silicone hydrogel lens seated on the top of the mold half to which it is adhered, wherein the suction cup also connecting with a central channel which can be switched from vacuum pressure to compressed gas or vice versa, a pin-pushing device, wherein the pin-pushing device is located below the mold holder and has a pin; wherein the mold holder can be lowered to against the pin, thereby the pin deforms a surface of the one of the female mold half or the male mold half.
- FIG. 1 is a cross-sectional view of a mold according to a preferred embodiment of the invention.
- FIG. 2 illustrates schematically a process for separating the male and female mold halves of a lens-forming mold according to the invention and an apparatus for performing a method of the invention.
- FIG. 3 illustrates a vacuum device with a suction cup.
- FIG. 4 illustrates a suction cup holding a contact lens which adhered to a mold half and a pushing pin located below, but not engaging to, the suction cup.
- FIG. 5 illustrates the pushing pin applying a force to deform the mold half which a contact lens attached to.
- FIG. 6 Illustrates the deformed the mold half rest on the push pin when the suction cup moves upwards.
- FIG. 7 Illustrates the contact lens drops off from the suction cup when the central channel is switched from vacuum to a compressed gas.
- hydrogel refers to a polymeric material which can absorb at least 10 percent by weight of water when it is fully hydrated. Generally, a hydrogel material is obtained by polymerization or copolymerization of at least one hydrophilic monomer in the presence of or in the absence of additional monomers and/or macromers.
- a “silicone hydrogel” refers to a hydrogel obtained by copolymerization of a polymerizable composition including at least one silicone-containing vinylic monomer or at least one silicone-containing macromer.
- a "vinylic monomer”, as used herein, refers to a low molecular weight compound that has an ethylenically unsaturated group and can be polymerized actinically or thermally. Low molecular weight typically means average molecular weights less than 700 Daltons.
- actinically in reference to curing or polymerizing of a polymerizable composition or material means that the curing (e.g. , crosslinked and/or polymerized) is performed by actinic irradiation, such as, for example, UV irradiation, ionized radiation (e.g. gamma ray or X-ray irradiation), microwave irradiation, and the like.
- actinic irradiation such as, for example, UV irradiation, ionized radiation (e.g. gamma ray or X-ray irradiation), microwave irradiation, and the like.
- Thermal curing or actinic curing methods are well-known to a person skilled in the art.
- a “hydrophilic vinylic monomer”, as used herein, refers to a vinylic monomer which as a homopolymer typically yields a polymer that is water-soluble or can absorb at least 10 percent by weight water.
- a “hydrophobic vinylic monomer”, as used herein, refers to a vinylic monomer which as a homopolymer typically yields a polymer that is insoluble in water and can absorb less than 10 percent by weight water.
- a "macromer” refers to a medium and high molecular weight compound or polymer that contains ethylenically unsaturated groups and can be polymerized actinically or thermally.
- Medium and high molecular weight typically means average molecular weights greater than 700 Daltons.
- a "polymer” means a material formed by polymerizing/crosslinking one or more monomers, macromers and or oligomers.
- Molecular weight of a polymeric material refers to the number-average molecular weight unless otherwise specifically noted or unless testing conditions indicate otherwise.
- a "prepolymer” refers to a starting polymer which can be cured (e.g., crosslinked and/or polymerized) actinically or thermally to obtain a crosslinked and/or polymerized polymer having a molecular weight much higher than the starting polymer.
- a “lens-forming material” refers to a polymerizable composition which can be cured (i.e., polymerized and/or crosslinked) thermally or actinically to obtain a crosslinked polymer.
- Lens-forming materials are well known to a person skilled in the art.
- the invention is generally related to a method for separating mold and dislodging (or removing or de-blocking) of a silicone hydrogel contact lens from a mold after lens curing and before lens extraction.
- the invention is partly based on the discovery that use of deforming force, such as a straining/stretching force, or a compression force, applied against a non-optical surface of one of the mold halves, can be used efficiently to separate molds into mold halves and also used for dislodging a silicone-hydrogel lens from its adhering mold half, thereby increasing production yield.
- Methods of manufacturing mold sections for cast molding a contact lens are generally well known to those of ordinary skill in the art.
- the process of the present invention is not limited to any particular method of forming a mold. In fact, any method of forming a mold can be used in the present invention. However, for illustrative purposes, the following discussion has been provided as one
- a mold in general, includes at least two mold sections (or portions) or mold halves, i.e. male and female mold halves.
- the male mold half defines a first molding (or optical) surface defining the posterior (concave) surface of a lens and the second mold half defines a second molding (or optical) surface defining the anterior (convex) surface of a lens.
- the first and second mold halves are configured to receive each other such that a lens forming cavity is formed between the first molding surface and the second molding surface.
- the molding surface of a mold half is the cavity-forming surface of the mold and in direct contact with lens-forming material.
- FIG. 1 schematically illustrates a preferred mold 100 used in the methods and apparatus of the invention.
- the mold 100 includes a female mold half 1 and male mold half 2.
- the male mold half 2 includes a base 61 , a substantially cylindrical body 25 which extends upward from base 61 , a generally convexly-shaped optical molding surface defining the posterior (concave) surface of a molded contact lens, and an annular shoulder 65 which surrounds the optical molding surface.
- the optical molding surface of the male mold half protrudes outward from the top of body 25.
- the annular shoulder 65 shown is flat. It is understood that the annular should 65 can have any suitable surface, such as, e.g. , a tilted surface.
- the male mold half also has a non-optical mold surface, which is the generally concave-shaped area or surface on the opposite side from the convexly-shaped optical molding surface.
- the female mold half 1 includes a base 51 , a substantially cylindrical body
- the optical molding surface of the female mold half recesses downward from the top of the body 15.
- Collar 4 (or up-protruding flange) is preferably integral part of the female mold half 1 and protrudes upward from the top of the body 15.
- a circumferential groove (or recessed area) 1 1 is formed on top of the body 15 outside of the optical molding surface and functions as an overflow for any excess polymerizable lens-forming material.
- the female mold half also has a non-optical mold surface, which is the generally convexly-shaped area or surface on the opposite side from the concave-shaped optical molding surface.
- the term "collar” as used herein refers to a peripheral circular part which protrudes upward from the top of body of one of the two mating mold halves.
- a collar can be attached to or preferably be an integral part of that mold half and which can encircle the other mold half to provide a tight seal between the two mold halves. It is understood that the collar can be provided on either of the male and female mold halves.
- mold halves 1 and 2 are configured to receive each other such that a contact lens forming cavity 12 is formed between the optical molding surfaces of the male mold half and the female mold half.
- the collar 4 encircles the body 25 of the male mold half 2 to provide a tight seal 5 between the female and male mold halves when the mold is closed.
- mold halves 1 and 2 can be first injection molded from a plastic resin in an injection molding apparatus, as well known to a person skilled in the art.
- a specific amount, e.g. an amount sufficient to fill the mold cavity without introducing too much waste, of a polymerizable lens-forming material is typically dispensed into the female mold half 1 by means of a dispensing device.
- the male mold half 2 is put on and the mold 100 is closed (FIG. 1 ).
- the mold 100 closes, if there is any excess polymerizable lens-forming material, it will be pressed into an overflow area 1 1 provided on the female mold half 1 .
- the closed mold 100 containing the polymerizable lens- forming material is subjected to actinic irradiation (e.g. , UV radiation or visible light radiation), or heat radiation, at least in the region of the lens forming cavity 12.
- actinic irradiation e.g. , UV radiation or visible light radiation
- at least one of the mold halves is transparent to the actinic radiation (e.g. , UV light) at least in the region of the molding surface.
- actinic radiation e.g. , UV light
- the polymerizable lens-forming material in the lens forming cavity 12 is polymerized. It is also possible for any polymerizable lens-forming material in the overflow area 1 1 to be polymerized.
- the mold halves can be formed through various techniques, such as injection molding. Methods of manufacturing mold halves for cast-molding a contact lens are generally well known to those of ordinary skill in the art.
- the process of the present invention is not limited to any particular method of forming a mold. In fact, any method of forming a mold can be used in the present invention.
- the first and second mold halves can be formed through various techniques, such as injection molding or lathing. Examples of suitable processes for forming the mold halves are disclosed in U.S. Patent Nos. 4,444,71 1 to Schad; 4,460,534 to Boehm et al. ; 5,843,346 to Morrill; and 5,894,002 to Boneberqer et aL , which are also incorporated herein by reference.
- Virtually all materials known in the art for making molds can be used to make molds for making contact lenses.
- polymeric materials such as polyethylene, polypropylene, polystyrene, PMMA, Topas® COC grade 8007-S10 (clear amorphous copolymer of ethylene and norbornene, from Ticona GmbH of Frankfurt, Germany and Summit, New Jersey), or the like can be used.
- Other materials that allow UV light transmission could be used, such as quartz glass and sapphire.
- a silicone hydrogel lens-forming material includes at least one silicon-containing monomer or macromer, or can be any lens formulations for making soft contact lenses.
- Exemplary lens formulations include without limitation the formulations of lotrafilcon A, lotrafilcon B, etafilcon A, genfilcon A, lenefilcon A, polymacon, acquafilcon A, balafilcon, senofilcon A, and the like.
- a lens-forming material can further include other components, such as an initiator (e.g. , a photoinitiator or a thermal initiator), a visibility tinting agent, UV- blocking agent, photosensitizers, and the like.
- a silicone hydrogel lens- forming material used in the present invention includes a silicone-containing macromer or prepolymer.
- silicone-containing vinylic monomers include, without limitation, methacryloxyalkylsiloxanes, 3-methacryloxy propylpentamethyldisiloxane, bis(methacryloxypropyl)tetramethyl-disiloxane, monomethacrylated
- polydimethylsiloxane mercapto-terminated polydimethylsiloxane, N- [tris(trimethylsiloxy)silylpropyl]acrylamide, N- [tris(trimethylsiloxy)silylpropyl]methacrylamide, tris(pentamethyldisiloxyanyl)-3- methacrylatopropylsilane (T2), and tristrimethylsilyloxysilylpropyl methacrylate (TRIS).
- TRIS tris(pentamethyldisiloxyanyl)-3- methacrylatopropylsilane
- T2 tristrimethylsilyloxysilylpropyl methacrylate
- a preferred siloxane-containing monomer is TRIS, which is referred to 3- methacryloxypropyltris(trimethylsiloxy) silane, and represented by CAS No.
- TIS also includes dimers of 3- methacryloxypropyltris(trimethylsiloxy) silane.
- siloxane-containing macromer with ethylenically unsaturated group(s) can be used to produce a silicone hydrogel material.
- a particularly preferred siloxane-containing macromer is selected from the group consisting of Macromer A, Macromer B, Macromer C, and Macromer D described in US
- Macromers that contain two or more polymerizable groups can also serve as cross linkers.
- polyakyleneoxides could also be of utility.
- Such macromers could be mono or difunctionalized with acrylate, methacrylate or vinyl groups.
- methacrylate end capped polyethyleneoxide-block- polydimethylsiloxane-block-polyethyleneoxide to enhance oxygen permeability.
- silicone-containing prepolymers examples include without limitation those disclosed in US Patent Application Publication No. US 2001 -0037001 A1 and US Patent No. 6,039,913, which are incorporated herein by references in their entireties.
- the prepolymers used in the invention are previously purified in a manner known p_er se, for example by precipitation with organic solvents, such as acetone, filtration and washing, extraction in a suitable solvent, dialysis or ultrafiltration, ultrafiltration being especially preferred.
- the prepolymers can be obtained in extremely pure form, for example in the form of concentrated aqueous solutions that are free, or at least substantially free, from reaction products, such as salts, and from starting materials, such as, for example, non-polymeric constituents.
- the preferred purification process for the prepolymers used in the process according to the invention can be carried out in a manner known p_er se. It is possible for the ultrafiltration to be carried out repeatedly, for example from two to ten times. Alternatively, the ultrafiltration can be carried out continuously until the selected degree of purity is attained. The selected degree of purity can in principle be as high as desired.
- a suitable measure for the degree of purity is, for example, the concentration of dissolved salts obtained as by-products, which can be determined simply in known manner.
- a silicone hydrogel lens-forming material can also include a hydrophilic vinylic monomer.
- a hydrophilic vinylic monomer that can act as a plasticizer can be used in the fluid composition of the invention.
- hydrophilic monomers are N,N- dimethylacrylamide (DMA), 2-hydroxyethylmethacrylate (HEMA), hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate (HPMA),
- a silicone hydrogel lens-forming material can also include a hydrophobic monomer. By incorporating a certain amount of hydrophobic vinylic monomer in a polymerizable fluid composition, the mechanical properties (e.g. , modulus of elasticity) of the resultant polymer may be improved.
- a silicone hydrogel lens-forming material can further include an
- antimicrobial agent preferably antimicrobial metal nanoparticles, and more preferably silver nanoparticles.
- a silicone hydrogel lens-forming material can be a solution or a solvent-free liquid or melt at a temperature below 90°C.
- a person skilled in the art will know well how to prepare silicone hydrogel lens-forming material.
- a silicone hydrogel lens-forming material can be a solution or a solvent-free liquid or melt at a temperature below 60°C.
- a specific amount of a polymerizable lens-forming material is typically dispensed into a female mold half by means of a dispensing device and then a male mold half is put on and the mold is closed. As the mold closes, any excess polymerizable lens-forming material is pressed into an overflow provided on the female mold half (or alternatively on the male mold half).
- the closed mold containing the polymerizable lens-forming material subsequently is cured.
- a person skilled in the art knows well how to cure a lens- forming material.
- a lens-forming material is subjected to actinic irradiation (e.g. , UV radiation) at least in the region of the lens forming cavity or thermal treatment (e.g. , heating in an oven) to form a lens.
- actinic curing at least one of the mold halves is transparent to the actinic radiation (e.g. , UV light) at least in the region of the molding surface.
- actinic radiation e.g. , UV light
- at least the polymerizable lens- forming material in the lens forming cavity is polymerized. It is also possible for any polymerizable lens-forming material in the overflow to be polymerized. This is advantageous in the respect that, when the mold is opened, the excess
- polymerized lens-forming material then remains in the overflow of the female mold half, while the contact lens adhering to the male mold half can be removed and further processed together with male mold half. Subsequently, applying a force to non-optical surface of the female mold at a location about the center area of non-optical molding surface at an angle of less than about 30 degrees, preferably less than about 10 degrees, most preferably less than about 5 degrees (i.e. , in a direction substantially normal to center area of non-optical molding surface) relative to the axis of the mold to deform the female mold surface which breaks the bonds between the optical molding surface of the female mold and the lens, as shown in FIG. 2.
- the demolding assembly includes a pin 70 positionable against the center area of non- optical molding surface of the female mold section.
- the pin 70 has a flat free end 70a to enable a surface contact between the free end 70a and the center area of non-optical molding surface of the female mold.
- the scope of the invention is not limited to such a particular flat configuration of the pin end 70a, for example the pin may have an outwardly rounded (convex) free end or concave-shaped free end, or other shape.
- the pin 70 is movable and the female mold remains stationary by applying a restraining force to female mold half applying a restraining force to female mold half with a first pry finger set 32 for maintaining the female mold half in a fixed position.
- the free end 70a of the pin 70 applies a longitudinally directed force to the central portion of the non-optical surface of the female mold.
- the first pry finger set 32 applies a counteractive force against the end face 51 a of the flange 51 of the female mold section 1 , retaining the flange in place. Consequently, the female mold section is deformed by a compression force between the free end 70a of the pin 70 and the first finger 32. This force deforms the curved part of the female mold section and breaks or loosens the adhesive bond between the lens-forming optical surface of the female mold section 1 and the anterior surface of the lens 12.
- a vertical lifting movement is applied to the male mold half with a second pry finger set (while maintaining the restraints on the female mold half so as to effectuate gradual separation between the female mold half and the male mold half.
- the contact lens After separating the male mold and the female mold, the contact lens generally adheres to the male mold even though the molding surfaces of the female mold and male mold are not treated before or after dispensing a specific amount of a polymerizable lens-forming material into one of the mold halves to render the molded contact lens preferentially adhered to the female mold or male mold when separating the mold.
- the mold After breaking the bond between the optical molding surface of the female mold half and the lens, the mold is separated, with the molded contact lens adhering to the male mold half 2. It is surprising to find out that, according to the present invention, the molded contact lens adheres to the male mold half even though the molding surfaces of the female mold and male mold need not be treated to render the molded contact lens preferentially adhered to the female mold half or the male mold half when separating the mold.
- the lens will generally be adhered to the optical surface of the male mold section, when the initial deforming force is applied against the non-optical surface of the female mold half, and must therefore be released from (removed from) the male mold section.
- the lens typically remains adhered to the male mold section.
- the deforming force can be applied against the non-optical surface male mold half as a stretching or straining force applied along the longitudinal axis of the male mold half to deform the male mold half, while it is held in place by the first set of pry fingers. This breaks the bonds or adherence between the optical molding surface of the male mold half and the lens, thereby the lens adheres to the female mold when separating the mold.
- Figs 3-7 illustrate a delensing process and apparatus.
- FIG. 3 illustrates a part of delensing device (200) comprises a suction cup (203) and a mold half holder (201 ).
- the suction cup connects with a central channel (202) which can be switched from vacuum pressure to compressed gas or vice versa.
- the compressed gas can be air or an inert gas such as nitrogen, etc.
- a mold half holder (201 ) is also connects to the suction cup for holding a molded silicone hydrogel contact lens attached to the one of the female mold half or the male mold half with the central channel switches set to vacuum pressure.
- the suction cup (203) is structured to contact the molded silicone hydrogel lens seated on the top of the mold half to which it is adhered without damaging the product, and may be formed from any suitable material such as soft rubber, silicone rubbers, or polymeric foam-type materials.
- FIG. 4 illustrates a mold half holder holding a molded silicone hydrogel lens (600) which is adhered to a mold half (400) and a pushing pin (300) located below, but not engaging to, the suction cup.
- FIG. 5 illustrates the pushing pin (300) applying a force to deform the mold half (400) to which a contact lens is attached.
- the free end 300a of the pin 300 applies a longitudinally directed force to the central portion of the non-optical surface of the male mold half.
- the force deforms the curved part of the male mold section and breaks the adhesive bond between the lens-forming optical surface of the male mold half and the anterior surface of the lens.
- the push pin strikes the central portion of the non-optical surface of the male mold half up to 3 times.
- FIG. 6 illustrates the deformed mold half (500) rests on the push pin when the suction cup moves upwards and the suction cup continues to hold the molded silicone hydrogel contact lens.
- FIG. 7 Illustrates the contact lens drops off from the suction cup when the central channel switches from vacuum to compressed gas to blow the molded silicone hydrogel contact lens away from the suction cup.
- the lens may be subjected to further processing (e.g. , extraction, hydration, any coatings or other treatments, sterilization and the like).
- further processing e.g. , extraction, hydration, any coatings or other treatments, sterilization and the like.
- Figs. 3-7 illustrate the process and apparatus for dislodging (delensing) a molded contact lens which is attached to a male mold half as an example.
- the process and apparatus can be used to dislodge (delens) a molded contact lens attached to a female mold half.
- the pin applies a force to the concave external surface (non-optical surface) of the male mold half to loosen the lens so that it can be removed by the suction cup.
- the pin For dislodging (delensing) a molded contact lens attached to a female mold half, the pin will apply a force to the convex external surface (non-optical surface) of the female mold half instead, to loosen the lens from the female mold half so that it can be removed by the suction cup.
- the invention is directed to An apparatus for delensing silicone hydrogel contact lenses from the lens adhering mold half, the apparatus comprising: a mold half holder, wherein the mold half holder holding a molded silicone hydrogel contact lens seated on the top of one of the female mold half or the male mold half, a suction cup, wherein the suction cup connecting with the mold half holder and contacting the molded silicone hydrogel lens seated on the top of the mold half to which it is adhered, wherein the suction cup also connecting with a central channel which can be switched from vacuum pressure to compressed gas or vice versa, a pin-pushing device, wherein the pin-pushing device is located below the mold holder and has a pin; wherein the mold holder can be lowered to against the pin, thereby the pin deforms a surface of the one of the female mold half or the male mold half.
- FIG. 1 Various embodiments are evident. Although one mold (FIG. 1 ) is illustrated, the invention is in no way limited to this specific mold. A person skilled in the art can readily determine other molds for which the invention has applicability.
Abstract
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
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US201662408343P | 2016-10-14 | 2016-10-14 | |
PCT/IB2017/056332 WO2018069869A1 (en) | 2016-10-14 | 2017-10-12 | Method for producing contact lenses |
Publications (1)
Publication Number | Publication Date |
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EP3526017A1 true EP3526017A1 (en) | 2019-08-21 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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EP17797740.2A Pending EP3526017A1 (en) | 2016-10-14 | 2017-10-12 | Method for producing contact lenses |
Country Status (6)
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---|---|
US (1) | US11279103B2 (en) |
EP (1) | EP3526017A1 (en) |
CN (1) | CN109803815B (en) |
MY (1) | MY193031A (en) |
SG (1) | SG10202103737YA (en) |
WO (1) | WO2018069869A1 (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3526016A1 (en) * | 2016-10-14 | 2019-08-21 | Novartis AG | Method for producing contact lenses |
SG11202009916RA (en) | 2018-06-04 | 2020-12-30 | Alcon Inc | Method for producing silicone hydrogel contact lenses |
EP3802081B1 (en) | 2018-06-04 | 2023-03-01 | Alcon Inc. | Method for producing silicone hydrogel contact lenses |
Family Cites Families (52)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1570359B2 (en) * | 1964-07-02 | 1970-12-10 | Ceskoslovenskä akademie v§d, Prag | Process for the manufacture of contact lenses |
US4136250A (en) * | 1977-07-20 | 1979-01-23 | Ciba-Geigy Corporation | Polysiloxane hydrogels |
US4153641A (en) * | 1977-07-25 | 1979-05-08 | Bausch & Lomb Incorporated | Polysiloxane composition and contact lens |
DE2839249A1 (en) * | 1977-09-12 | 1979-03-22 | Toray Industries | METHOD OF MANUFACTURING A SOFT CONTACT LENS AND OUTPUT SOLUTION FOR CARRYING OUT THE METHOD |
FR2449519A1 (en) * | 1979-02-23 | 1980-09-19 | Essilor Int | ANNULAR JOINT FOR MOLDING OPHTHALMIC OR OPTICAL LENSES IN ORGANIC MATERIAL, AND METHOD FOR IMPLEMENTING SUCH A JOINT |
US4444711A (en) | 1981-12-21 | 1984-04-24 | Husky Injection Molding Systems Ltd. | Method of operating a two-shot injection-molding machine |
US4460534A (en) | 1982-09-07 | 1984-07-17 | International Business Machines Corporation | Two-shot injection molding |
US4680336A (en) * | 1984-11-21 | 1987-07-14 | Vistakon, Inc. | Method of forming shaped hydrogel articles |
CA1263208A (en) | 1985-12-19 | 1989-11-28 | Kirk K.S. Hwang | Method and apparatus for making optical devices |
GB8601967D0 (en) | 1986-01-28 | 1986-03-05 | Coopervision Optics | Manufacturing contact lenses |
US4740533A (en) * | 1987-07-28 | 1988-04-26 | Ciba-Geigy Corporation | Wettable, flexible, oxygen permeable, substantially non-swellable contact lens containing block copolymer polysiloxane-polyoxyalkylene backbone units, and use thereof |
DE68923345T2 (en) | 1988-11-02 | 1995-12-21 | British Tech Group | Pouring contact lenses. |
US4889664A (en) * | 1988-11-25 | 1989-12-26 | Vistakon, Inc. | Method of forming shaped hydrogel articles including contact lenses |
US4931228A (en) | 1989-04-05 | 1990-06-05 | Coastvision | Method of manufacturing soft contact lens buttons |
US5160749A (en) * | 1990-10-30 | 1992-11-03 | Minnesota Mining And Manufacturing Company | Three piece mold assembly for making an ocular device |
US5264161A (en) * | 1991-09-05 | 1993-11-23 | Bausch & Lomb Incorporated | Method of using surfactants as contact lens processing aids |
US5271875A (en) * | 1991-09-12 | 1993-12-21 | Bausch & Lomb Incorporated | Method for molding lenses |
US5260000A (en) * | 1992-08-03 | 1993-11-09 | Bausch & Lomb Incorporated | Process for making silicone containing hydrogel lenses |
EP0657264B1 (en) | 1993-12-13 | 1999-07-21 | Novartis AG | Process and device for the production of a contact lens |
US5894002A (en) | 1993-12-13 | 1999-04-13 | Ciba Vision Corporation | Process and apparatus for the manufacture of a contact lens |
US5850107A (en) | 1994-06-10 | 1998-12-15 | Johnson & Johnson Vision Products, Inc. | Mold separation method and apparatus |
IL113826A0 (en) | 1994-06-10 | 1995-08-31 | Johnson & Johnson Vision Prod | Method and apparatus for demolding ophthalmic contact lenses |
US6012471A (en) | 1994-06-10 | 2000-01-11 | Johnson & Johnson Vision Products, Inc. | Automated method and apparatus for single sided hydration of soft contact lenses in package carriers |
US5843346A (en) | 1994-06-30 | 1998-12-01 | Polymer Technology Corporation | Method of cast molding contact lenses |
US5760100B1 (en) | 1994-09-06 | 2000-11-14 | Ciba Vision Corp | Extended wear ophthalmic lens |
US5693268A (en) | 1996-04-01 | 1997-12-02 | Johnson & Johnson Vision Products, Inc. | Wedge demolding of cast lens mold assemblies |
US5820895A (en) | 1996-06-04 | 1998-10-13 | Johnson & Johnson Vision Products, Inc. | Conductive probe for heating contact lens mold assemblies during demolding |
DE69713793T2 (en) | 1996-11-06 | 2002-11-07 | Bausch & Lomb | METHOD AND DEVICE FOR REMOVING CONTACT LENSES MOLDED PARTS |
US6007229A (en) | 1997-06-05 | 1999-12-28 | Johnson & Johnson Vision Products, Inc. | Rapid robotic handling of mold parts used to fabricate contact lenses |
US6039913A (en) | 1998-08-27 | 2000-03-21 | Novartis Ag | Process for the manufacture of an ophthalmic molding |
AR021819A1 (en) | 1998-09-30 | 2002-08-07 | Novartis Ag | APPARATUS AND METHOD FOR CLEANING OPHTHALM COMPONENTS |
FR2795314B1 (en) | 1999-06-25 | 2002-06-14 | Oreal | DETERGENT COSMETIC COMPOSITION COMPRISING A SILICONE AND AN AMPHOTERIC FAT CHAIN POLYMER AND USE |
US6638451B1 (en) * | 1999-08-31 | 2003-10-28 | Novartis Ag | Plastic casting molds |
JP4791669B2 (en) | 1999-10-27 | 2011-10-12 | ノバルティス アーゲー | Contact lens deblocking |
ES2222373T3 (en) | 2000-03-24 | 2005-02-01 | Novartis Ag | RETICULAR OR POLYMERIZABLE PREPOLIMEROS. |
US6558584B1 (en) | 2000-03-31 | 2003-05-06 | Bausch & Lomb Incorporated | Apparatus and method for handling an ophthalmic lens |
US6347870B1 (en) * | 2000-03-31 | 2002-02-19 | Bausch & Lomb Incorporated | Handling assembly for fluid processing of ophthalmic lenses |
GB2360730B (en) | 2000-03-31 | 2004-09-22 | Bausch & Lomb Uk Ltd | Apparatus and method for separating contact lens molds |
US6663801B2 (en) | 2001-04-06 | 2003-12-16 | Johnson & Johnson Vision Care, Inc. | Silicon carbide IR-emitter heating device and method for demolding lenses |
JP2003011140A (en) * | 2001-07-04 | 2003-01-15 | Canon Inc | Method and apparatus for demolding diffraction optical element |
JP4695797B2 (en) * | 2001-09-28 | 2011-06-08 | 株式会社メニコンネクト | Lens mold opening means and method |
US20040061246A1 (en) | 2002-09-30 | 2004-04-01 | John Cardiff | Method and apparatus for dry releasing lenses from an anterior mold half |
WO2005011966A1 (en) | 2003-07-24 | 2005-02-10 | Provis Limited | Methods and apparatus for use in contact lens manufacture and packaging |
GB2409427A (en) * | 2003-12-23 | 2005-06-29 | Bausch & Lomb | Handling moulded opthalmic lenses |
DE602005006996D1 (en) | 2004-03-24 | 2008-07-03 | Novartis Ag | PROCESS FOR THE PRODUCTION OF CONTACT LENSES |
US20060202367A1 (en) * | 2005-03-11 | 2006-09-14 | Knutzen Josef V | Multi stage ophthalmic lens demold |
CN102123853B (en) * | 2008-08-20 | 2014-09-10 | 诺华股份有限公司 | Apparatus for removing an ophthalmic lens from a mold half |
SG10201405462TA (en) * | 2009-09-04 | 2014-10-30 | Novartis Ag | Gripper for a contact lens and process for transporting a contact lens |
HUE042855T2 (en) * | 2009-10-16 | 2019-07-29 | Novartis Ag | Process and apparatus for manufacturing an ophthalmic lens |
JP5428005B2 (en) * | 2009-11-12 | 2014-02-26 | 株式会社メニコンネクト | Method for separating ophthalmic lens mold and apparatus used therefor |
US20140175685A1 (en) * | 2012-12-20 | 2014-06-26 | Novartis Ag | Method for Making Silicone Hydrogel Contact Lenses |
EP3526016A1 (en) * | 2016-10-14 | 2019-08-21 | Novartis AG | Method for producing contact lenses |
-
2017
- 2017-10-12 CN CN201780061637.3A patent/CN109803815B/en active Active
- 2017-10-12 MY MYPI2019000789A patent/MY193031A/en unknown
- 2017-10-12 EP EP17797740.2A patent/EP3526017A1/en active Pending
- 2017-10-12 US US15/782,579 patent/US11279103B2/en active Active
- 2017-10-12 SG SG10202103737YA patent/SG10202103737YA/en unknown
- 2017-10-12 WO PCT/IB2017/056332 patent/WO2018069869A1/en unknown
Also Published As
Publication number | Publication date |
---|---|
US20180104920A1 (en) | 2018-04-19 |
WO2018069869A1 (en) | 2018-04-19 |
US11279103B2 (en) | 2022-03-22 |
CN109803815A (en) | 2019-05-24 |
SG10202103737YA (en) | 2021-05-28 |
CN109803815B (en) | 2021-06-11 |
MY193031A (en) | 2022-09-23 |
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